New concept of a compact multiwavelength solid state laser for laser-induced shock wave lithotripsy

摘要

In the past a widespread use of pulsed solid-state and flashlamp-pumped pulsed dye lasers in the vast medical field of endoscopic laser-induced shock wave lithotripsy (LISL) of urinary, biliary, and salivary stones was hindered mainly by the facts that (1) the available systems were too expensive compared to other conventional therapies; (2) the laser systems of the first generation didn't ideally fit into existing operation rooms because they were bulky and heavy; (3) the laser systems - except for the non solid-state dye laser system - provided only a fixed wavelength for stone fragmentation. This paper reports on a new concept of a small size pulsed and tunable alexandrite laser system for laser-induced shock wave lithotripsy that could provide not only wavelengths in the fundamental region of 720-860 nm with high peak powers and high energy fluences but also in the frequency-doubled region of 360-430 nm. The fragmentation process is induced via the violet wavelengths and the fragmentation efficiency is reinforced via the fundamental wavelengths of the laser system.